package lv.id.jc.piglatin.core;
   
   import java.util.function.Function;
   import java.util.regex.Matcher;
   import java.util.regex.Pattern;
   
   import org.springframework.stereotype.Component;
   
   /**
   * This class is responsible for matching words in a given phrase.
   */
  @Component
  public class WordsMatcher implements Function<String, Matcher> {
      private static final Pattern WORD = Pattern.compile("""
              # A word contains only Unicode letters and apostrophe (') in the middle
              (               # Start of the group
                  \\p{L}      # Any Unicode letter
              |               # OR
                  (?<=\\p{L}) # Positive lookbehind for a Unicode letter
                  '           # An apostrophe
                  (?=\\p{L})  # Positive lookahead for a Unicode letter
              )+              # One or more of the previous group
              """,
          Pattern.COMMENTS + Pattern.CASE_INSENSITIVE);
  
      /**
       * This method applies the word-matching pattern to a given phrase.
       * It returns a Matcher object that can be used to find words in the phrase.
       *
       * @param phrase the phrase to apply the word-matching pattern to
       * @return a Matcher object for finding words in the phrase
       */
      @Override
      public Matcher apply(String phrase) {
          return WORD.matcher(phrase);
      }
  }